The present invention relates to a cooking appliance having a cooking compartment.
A prior cooking appliance, for example, a microwave oven having a cooking compartment and oven cooking function, has a cooling fan. When a user uses the oven cooking function, the temperature within the cooking compartment and around components positioned in an outer case of the oven rises. After oven cooking is finished, the cooling fan cools the components so that their temperature does not exceed their tolerance level.
The cooling time is determined in any of three ways. First, a temperature sensor is positioned adjacent a component which has the lowest temperature tolerance. Until the sensor detects that the temperature is under the tolerance level, the cooling fan continues to cool the components.
Second, a temperature sensor is positioned in the cooking compartment so that the sensor detects the temperature within the cooking compartment. Until the sensor detects that the temperature is less than a predetermined temperature, the cooling fan continues to cool the components. The predetermined temperature is set to a presumptive value at which the temperature of all components is presumed to be under the tolerance level.
Third, a cooling time is determined in accordance with the temperature set by a user for oven cooking. The cooling fan cools the components for the determined cooling time.
However, the first approach requires the sensor to be attached to the component, increasing manufacturing costs.
With the second approach, if a door to the cooking compartment is opened while the cooling fan is actuated, the temperature within the cooking compartment drops rapidly. As a result, since the temperature drops under the predetermined temperature, the cooling fan stops cooling the 10 components. Although the temperature drops under the predetermined temperature, the temperature of the components often does not drop enough. As a result, the cooling time is too short.
With the third approach, if the door is open while the cooling fan is running, the compartment is efficiently cooled by the outside air. As a result, although less cooling time is required, the cooling fan continues to run. Therefore, the cooling fan operates unnecessarily for a certain time.